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Question 711
Obstetric infection → Viral
Classification
Question
SSBAQuestion Header
Timing of antiviral post-exposure prophylaxis
Question Stem
A non-immune pregnant woman has had significant exposure to chickenpox. Oral aciclovir is selected for post-exposure prophylaxis. During which period should the antiviral prophylaxis be given?
Options
A
Days 1–5 after exposure
B
Days 7–14 after exposure
C
Days 3–7 after exposure
D
Days 14–21 after exposure
E
Only after a rash develops
Explanation
Oral aciclovir or valaciclovir used as post-exposure prophylaxis should be given from day 7 to day 14 following exposure. This timing distinguishes prophylaxis from treatment of established chickenpox. If a rash develops, the woman should be managed according to the recommendations for clinical maternal infection.
Option Validity
A) this is earlier than the recommended PEP interval.
C) prophylaxis starts from day 7 after exposure.
D) this delays initiation beyond the recommended starting point.
E) development of a rash represents established infection rather than the indication to start PEP.
Further Reading
RCOG Green-top Guideline No. 13, Chickenpox in Pregnancy, section 4.3.